Tranemission gearing



March 15,1927; 1,620,855

. c. E. F. AHLM.

I I TRANSMISSION. GIEARING Filed Dec. 1924 2 Sh'eets-'-Sheec 1 Y I cmgawmw 7 other.

s n. n. Auras, on CLEVELAND, onro, Assronon T0 acre-norms l arner I scanned comramz, or CLEVELAND, 01110, A oonronarxonprnnrswann.

Y TRA'HEMISQION GEAR ING.

Application filed December 30,1994. Serial No. 758,941.

This invention relates to transmission gearing such as used,- for' example, in automobile transmissions to secure awplurahty of speeds between the/motor and rear axle or:

driven member.- The gearing comprises essentially a gearing connection between driving and driven members including an internal external gear member mounted on an ecoentricbearing and meshing internally with a spur gear rigid with one of the members and external- 1y with a gear drivin ly connected with the It also inclu es means for controllin the rotation of the eccentric bearing.

'fiie general objects of the invention are to secure simplicity, cheapne'ss of construction, and compactness consistent with strength whereby the weight of the arts is reduced to a minimum. Another 0 ject is to provide a mechanism for connecting relatively moving members together which ma be easy and sure of operation yet which W} 1 not subject any of the parts of the gearing to sudden shock, or result in a noisy clas mg when operated to change from one speed to another. A further object includes, in the arrangement of such a gearing, the provision of mechanism for controlling the eccentrically mounted-internal external ear for accomplishing the reverse motion etween the driving and. driven member."

Further objects and advantages embodied in this invention will become apparent in the following description, having reference to the drawin s wherein I have illustrated the preferred orm.

' adapted to be connected to and disconnected from the engine and which may be termed the driving member is indicated at 1; 2 is the driven member adapte'd to be connected, in the form shown, with thespcopeller shaft,

leading to the rear-axle. "Ais'uitable casing is shown as comprising parts Azand 5 secured together by suitable fis'ing'cs embracing the flange of the'spider or hearing support member 6, the right hand portion of the'cas ferred toes the internal external. gear and preferably is carried upon separate bearings, designated 12, having their support on the rotatable eccentric bearing'member 15 shown as surrounding the driving member. The gear P is shown as meshing with an internal ear P rigid with a suitable flanged mem er 18, which isin turn rigid with the ropeller shaft. This gear P will be reerred to as the pro eller ear.

The means for ho dingt e composite gear against rotation yet permitting it to revolve, byreason of the free rotation of its bearing 15, includes a wheel 20 having a brake surface at 24: and a hub member 21. Offset cranlcmembers designated 27 each having hearings in a flange 28 rigid with the eomposite gear and in the web of the brake I whecl 20 connect the cqim'posite gear to the wheel. The oilset of these cranks corresponds to the amount of eccentricity of the eccentric bearing whereby'the'y may revolve idly when the hearing is held stationary or may positively prevent relative rotation between the composite gear and-the casing while permitting the gear to revolve whena brake 25 is applied to the, exterior of'the wheel 20.

For another condition, it is desired, towntrol or stop the rotation of the eccentric,

hearing, I have shown means for accomplishlng this comprisinga friction clutch one member of whichis carried by the ec-.

centric. The other member may for the p'esent purposes be considered as capable of mg held stationary, as though attached to thej 'vc asing. I have however shown it as begfjdapted to connect with one of a pair 0t ariiiatiires bfan electric transmission, such as sh'own in'my. prior Patent No. 1,515,322.

By reason of such connection, the bearing 15 ma be held against rotation'or independ enty rotate d. For the present purpose it will be assumed that such armature or equivalent means has no function other than to hold the bearing stationary. The bearing his shown as having a tubular portion 30 to whichis splined, or otherwise rigidlv secured, a counterweighted Wheel 31. The

lit

till

wheel has an interior clutching surface 32 which cooperates with expanding members l have shown two of these members each having inwardly projecting tongues 34 which rest in channel shaped guides 35 carried by a spider 36 which may be assumed to be rigid with the armature referred to.

Means such as radial tongues 37 project into shaft 1 arid separated brim portions 47, exv tending forwardly through openings in the spider member, which are embraced by a.

shifting collar 4.8 arranged to cooperate with an arm 4:9. To operate upon this cup memher I have shown a compression spring 50 bearing against a. portion of the spider at one end and against the bottom of the cap member 45 at the other wherefore the arm 49 acts merely to hold the spring inactive which'will upon being released. push, rearwardly on the arms 42 to operate the clutch and stop or hold the eccentric against rotation.

The above described mechanism may be operated to eiiect either a. reduced forward speed or a. still slower reverse condition of IOtitillOll between the engine shaft and proel er.

p It will be easily seen that 1" may also employ the clutching mechanism which I have shown to connect the driving or driven shaft with the eccentric and thus drive direct, that is with all the parts locked together and traveling at the same s eed. llhis however would necessitate provi ing a modified construction whereby the eccentric bearing might also be held stationary when, a simple reduction of speed of the propeller is desired in the same direction as the engine shaft. Such a construction is illustrated in my copending application, Ser. No. 758,940.

In the proportions shown and assuming a constant engine s eed, thefirstcondition of rotation may be t at at which the propeller is idle, that is with the brake 25 released and the clutch member if) withdrawn as shown.

" The pinion P now drives the composite gear ren ers enga *ement with the wheel iii, the eccentric will e graduallyslowed down and stopped and a second condition will obtain. The gear P would drive the gear P at at reduced speed and the gear P woulddrive the propeller at;

a still further reduced speed.

Fora third condition the brake 25.5 is are plied and thefclutch 45 released. The com posite car then simply revolves on its hear mg wit rout rotating. Because of the geared connection (21, P?) the gear teeth of P are v now pushed along by the revolving compos ite gear in the direction in which the eccen-v tric rotates, namely reverse to that of the can gins shaft. I have found the proportions shown give a slow enough reverse condition to be very satisfactory.

From the foregoing description it wilihe seen that I have provided. a very compact gearing which may be easily menutactured and assembled and'which is capable of speed ing member hiiving a pinion, a driven nieni her, a composite gear in mesh with said pinion and-"surrounding one of said men1- hers, an eccentric bearing for said gear capable of independent rotation relative to the driving member and of being held against rotation, a driven member having ageared connection with said composite gear, means for; preventing the rotation of said composite gear while permitting-it to re volve upon the. eccentric bearing when-the bearing is free to rdtate for transmitting one speed to the, driven member, and means including an expcndin friction clutch for holding'the eccentric caring-for an additional speed.

2. In a'tran'smission gearing, in combination, a driving member, a driven member, a. rotatable and revoluble composite gear in offset axial relation thereto end havinga geared connection with both oi? said members, a bearing for said gear capable of rotating freely and of being held against rotation, means including a main ally actuated friction mechanism arranged to constrain the movement of said bearing 7 for impartinga given rotation to said driven member through said gear members, and l means including a'brake member and a series .of cranks pivoted to the brake member and composite gear, for preventing the rotation of said composite gear while per mitting it to circulate about its bearing for imparting areverse rotation to 'said driven member;

'ling the 'rotating movement of the composite gear while permitting the revolution thereof for eflecting a reverse rotation of- ;the driven member, cooperating .fricti0n members, one being rigid with the eccentric 0, bearing, and means for operating the trio-r tion members to control the movement of the eccentric bearing'for effecting a forward rotation of said driven member. I

4. In a gearing of the class described, an

25 internal-external reduction gear, a relarotatable eccentric bearing for suptively porting said gear, a driving member and a driven member each having-a geared connection with the internal-external gear, a

clutch member carried bysaid bearing and rigid therewith, a cooperating clutch mem- 3. In a transmission gearing, in combinaii )5 L v ber afrlinged to prevent relative rotation betW een-the bearing and cooperating member,a plurality of riction shoes carried by said cooperating clutch member, operating means therefore including shoe operatingv arms and anormally" retracted spring adapted to react against said arms when released.-

' 5. In .a gearingfin combination, a driving member haviiig a pinion, a composite "gear member in mesh with said pinion, an eccentric bearing member for said gear arranged to rotateand to be held relatively station-' ary, a driven member having a geared conv nection to said composite gear, a normally inactive spring operated clutch for holding the eccentric bearing against rotation for imparting a reduced speed to said driven member and means for retarding the rotation of said gear while permitting it to revolve upon the eccentric bearing, when the-bearing is free to rotate, for effecting reverse rotation [of the driven member.

a In testimony whereof, I hereunto afiix my signature. H

CHARLES F AHLM; 

